Flavor ingredient regulatory record
Hexanal
Hexanal is an aldehyde in the green family, FEMA GRAS under FEMA number 2557 (CAS 66-25-1). Its odor is green, grassy, fatty, leafy, unripe fruit.
- FEMA
- 2557
- CAS
- 66-25-1
- JECFA
- 92
- EU FL
- 05.008
- Formula
- C6H12O
- EC
- 200-624-5
GRAS status: FEMA GRAS, publication 3. Recorded by FDA in the Substances Added to Food inventory under CAS 66-25-1.
Structure
Identity
Also known as: Caproaldehyde, Caproic aldehyde, Capronaldehyde, Hexaldehyde, n-Hexanal, n-Caproaldehyde, Hexylaldehyde, n-Capronaldehyde, Hexanaldehyde, n-Hexylaldehyde, NSC 2596, caproaldehyde.
Can Hexanal be labeled natural?
Nature makes hexanal, which is why the US label turns on process. A natural route gives natural flavor; synthesis gives artificial hexanal, same molecule. The EU and UK grant the natural claim only to that natural route; Mercosur and Mexico call synthetic material identical-to-natural.
- United States
- Natural or artificial, by process
- European Union and UK
- Natural only from natural material
- Mercosur and Mexico
- Natural or identical-to-natural
How each market defines the classes: natural vs artificial flavor under 21 CFR 101.22.
Regulatory status, with citations
United States
Hexanal is FEMA GRAS under FEMA number 2557. It is cited in the Code of Federal Regulations at 21 CFR 172.515.
European Union and United Kingdom
Listed on the Union List of flavouring substances as FL 05.008, Annex I Part A under Regulation (EC) 1334/2008, evaluation status approved (JECFA). The UK retains the same list.
JECFA (WHO / FAO)
JECFA number 92, evaluated at the 49th meeting in 1997. no safety concern at current levels of intake.
Other US flags
Not on the California Proposition 65 list.
TSCA Inventory status
A flavor ingredient is also an industrial chemical. Hexanal appears on the EPA Toxic Substances Control Act Chemical Substance Inventory under CAS 66-25-1, where EPA names it Hexanal.
Active in US commerce
EPA designates this substance active, so no Notice of Activity Form B is required before manufacturing. What active and inactive mean.
EPA publishes no regulatory flags on this listing. What the flags mean.
From the EPA non-confidential TSCA Inventory, July 2026 release. EPA also maintains a confidential portion it does not publish. Search the Inventory by CAS number.
Odor and taste
Odor: Green, grassy, fatty, leafy, unripe fruit.
Taste: Green, grassy, slightly fruity.
Where it is used
Hexanal is used in green notes, vegetable and apple, typically as a green note.
Structurally similar flavor ingredients
Flavor ingredients with a GRAS determination closest to Hexanal by structure. Whether one can replace it is a sensory and regulatory call; the reformulation tool works that through.
| Material | FEMA | Similarity | Occurrence |
|---|---|---|---|
| cis-3-Hexenal | 2561 | 97% | In nature |
| 3-Hexenal | 3923 | 97% | In nature |
| cis-4-Hexenal | 3496 | 96% | In nature |
| trans-4-Hexenal | 4046 | 96% | In nature |
| 2-Hexenal | 2560 | 96% | In nature |
More aldehydes in this index
2-Hexenal · 3-Hexenal · 2-Benzofurancarboxaldehyde · alpha-Butylcinnamaldehyde · Vanillin · 4,7-Decadienal
Hexanal FAQ
Does hexanal have FEMA GRAS status?
Hexanal holds FEMA GRAS status under FEMA number 2557. The Code of Federal Regulations lists it at 21 CFR 172.515.
How do I cite hexanal by FEMA or CAS number?
Cite hexanal as FEMA 2557 or CAS 66-25-1; both point to the same entry. Its flavor category is green.
What does hexanal smell and taste like, and where is it used?
The odor of hexanal is green, grassy, fatty, leafy, unripe fruit. On the palate it is green, grassy, slightly fruity. Typical uses are green notes, vegetable and apple.
What did JECFA conclude about hexanal?
JECFA evaluated hexanal at the 49th meeting in 1997 under JECFA number 92. The panel concluded: no safety concern at current levels of intake.
Can hexanal be used in the EU and UK?
Yes. FL 05.008 is the Union List entry for hexanal, annex I Part A, under Regulation 1334/2008, and the UK keeps the same list.
Can hexanal be labeled a natural flavor?
The process decides for hexanal. It occurs in nature, so a natural-source, natural-process material is natural flavor in the US and synthetic hexanal is artificial. The EU and UK grant the natural claim only to that natural route; Mercosur and Mexico call synthetic material identical-to-natural.
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Sources and attribution. The identity and regulatory facts on this page are taken from the FDA Substances Added to Food inventory, a US government record, which lists this substance as HEXANAL under CAS 66-25-1 and carries its FEMA number, its JECFA flavor number and its 21 CFR citations. The inventory is searchable at FDA. FDA records its technical effect as flavoring agent or adjuvant.
A FEMA GRAS conclusion is reached by the Expert Panel of the Flavor and Extract Manufacturers Association of the United States, and the FEMA number names that conclusion. FEMA publishes its own entry for this substance in the FEMA Flavor Library, which is the authoritative record of what the Panel decided and is worth reading alongside this page.
Ambrose Compliance is not affiliated with, endorsed by, or sponsored by FEMA. FEMA and FEMA GRAS are used here as identifiers for a published regulatory determination, not as marks of any relationship between FEMA and Ambrose.
About this page. Facts come from the FDA Substances Added to Food inventory, the Code of Federal Regulations, the EPA TSCA Inventory, the EU Union List, JECFA and the Ambrose database, with FEMA's published determination cited where it applies; parts of the text are written by Ambrose AI, which can make mistakes. Check the cited source before relying on anything here. This is not regulatory or legal advice.